Vivus has reported positive results from a phase 2 study evaluating the safety and efficacy of Qnexa, an investigational drug, for the treatment of obstructive sleep apnea (OSA). Vivus recently completed phase 3 development of Qnexa for the treatment of obesity and submitted a New Drug Application (NDA) to the FDA for that indication.
The study demonstrated improvement in the apnea/hypopnea index (AHI – a measure of the severity of sleep apnea) in patients with OSA treated with Qnexa for 28 weeks. Qnexa-treated patients also experienced significant weight loss, improvements in blood pressure, and overnight blood oxygen levels, said the company.
Leland Wilson, chief executive officer of Vivus, said: “Obstructive sleep apnea is a serious condition with recognized cardiovascular and metabolic consequences, including premature death. Current treatment approaches are limited to devices or surgery. We know that substantial weight loss can significantly improve sleep apnea. These phase 2 data suggest that Qnexa, if approved for this indication, may be a promising treatment for OSA. We have submitted the study results for presentation at a scientific meeting. We also look forward to meeting with the FDA to discuss the results of this study and to determine the regulatory path for approval.”
The apnea/hypopnea index is the standard measure of OSA severity, indicating the number of apnea/hypopnea events per hour of sleep. The phase 2 study (OB-204) was a single-center, randomized, double-blind, placebo-controlled parallel group trial, including 45 obese men and women (BMI 30 to 40 kg/m2, inclusive), 30 to 65 years of age. Patients enrolled were diagnosed with OSA based on an AHI greater than or equal to 15 (moderate to severe) at baseline. In addition to receiving active or placebo drug, all patients were provided with an intensive lifestyle modification program.
Patients treated with Qnexa for 28 weeks had a 69% reduction in sleep apnea events. Qnexa treatment reduced the number of apnea/hypopnea events from a mean of 46 events per hour of sleep to 14, compared to placebo patients with a reduction from a mean 44 events per hour of sleep to 27 (ITT-LOCF p less than or equal to 0.001 active vs placebo). Patients lost 10.2% body weight, or 23.8 lbs in 28 weeks – compared to 4.3% for placebo patients, or 10.4 lbs, (ITT-LOCF p<0.001 active vs placebo).
Systolic blood pressure was reduced by 15 mm Hg in the Qnexa group from a mean of 138 mm Hg at baseline (ITT-LOCF p<0.04 active vs placebo) and mean overnight oxygen saturation was improved in Qnexa patients (p<0.014 active vs placebo). Qnexa treatment was well-tolerated with no serious adverse events reported in the Qnexa arm; the most common side-effects were dry mouth, altered taste and sinus infection.